Originally posted by Peter Daniel One reason he used such strong expressions might be your attitude toward the whole subject.

Yes, as well as basically poorly informed or educated statements such "there is no difference in sound between tubes" , "There is no need whatsoever to go ordering custom transformers for a simple preamp project!", or mass delusion because we hear differences. I have 20 years experience and qualifications in electronics (until recently I taught it at College), as well as having built and analysed and listened to these circuits myself, and formed opinions based upon that work, to have it dismissed out of hand by someone whom I feel has displayed little real knowledge or understanding of the subject (in this and other threads) is offensive and insulting. To do so without having done the work themselves is a reflection on them. My comments are based on theory as well as my own personal experience.

Do <i>I</i> know it all? Hell no. Every post someone makes around an area of audio design that interests me, I read and try to look at it with a fresh mind (beginners mind) and often research it further because I learn lots that way. Jocko's and Fred's posts (amongst others) on digital and SS, often give 'lightbulb' moments, and have me looking for more information to understand the subject better.
But I can't be bothered with someone who already thinks they know better. The information sought is not hard to find. (see Gunderz Tubecad link below)

As for the "ïdiocy" remark, I was referring to a topology, not Joel personally. I was typing up that post when he posted his schematic. Looking back at the thread now, I see he mentioned it earlier too. I don't recall reading that before the post of mine in question, but I may have as I was doing several other things at the time.

WRT fool.
From dictionary.com
<i>One who is deficient in judgment, sense, or understanding.</i> Predominantly the last is what I meant.

No,I don't think so.You're jumping to the wrong conclusions and Dice45 is just as wrong by concluding that no CF is any good.
I do agree however that given the context his statement is valid.
Running the common CF into a low impedance is no good.
The same can be said about the SRPP circuit.

This generalisation of topologies is naysaying and a gross misunderstanding of the hows and whys of the technology and how to implement it.

IMO all involved parties are guilty to a point.

Quote:

Also from another moderator:

I have suggested to Dice45 before that if he was commenting as a moderator he'd then add the moderator symbol to the comment so that one can clearly see the differerence.

Let it be noticed once again it leads to confusion if such interaction is not clearly distinguishable.

Moreover,let it be noticed too that when the other moderators interact it is clear,concise and to the point and you know exactly why and when they are fellow members adding a contribution/comment and when they wear the moderator hat.

Personnally I had trouble right from the start in the DIY TT thread where it was impossible to distinguish between the two modes of posting.
No need to tell you this just escalated into a sinbin.
It went as far as to Dice 45 handing over the judgement and further follow-up to a fellow moderator.
Everything went relatively smooth since.

Quote:

If you can't hear the difference,

There are instances and circumstances where people are not perceptive to differences whilst others are.
If I were to be in such a case I'd still keep an open mind and inform myself about the consensus in general.
By no means is it constructive to say then that there is no difference because I can not perceive it.

Quote:

Seems like there's no point in debate when people are shut up like that in public.

Sometimes a necessary evil.
In this particular case,knowing the players involved and the topic at hand I can only say none of them is right.None.

It is however hard to judge when you're not involved in a thread from start to finnish.

Easy to jump to conclusions:

Brett feels offended by Joel proposing his headphone amp not ideally thought out as a preamp.
Being this Joel's own "brainchild" he takes offense at it and Joel perceives it as being treated as a "fool" even as an "idiot"

Let me tell you that was not what Brett meant: Joel was a bit hasty to present his new baby and it would have been wiser had he just started a thread on his own.

Right from the start in this thread there was diversion of opinion on what to present to the person asking in the first place.

I notice it so often: someone starts a thread and the only person you're never going to see again is..you guessed it.
Moreover the question at hand is so vague and open that it makes me wonder whether any real interest exists.
I've been around for too long in the business not to recognize old tricks.

This may very well not be the case so I leave it open.

To recap:

I see a lot of generalization on all sides as to whether or not a given circuit is good or not,worst of all there's a lot of lack of understanding on how circuitry interacts once it gets hooked up to another.

Hey,look at it this way:I did have some making up to do for some stolen quick posts,right?

Shall we be civilized?

Ta,

P.S Gunderz,thx.Tthat link is pointing in the right direction.Just hope someone is going to read it.

If you can't hear the difference,
"You should rather keep it to yourself"

Seems like there's no point in debate when people are shut up like that in public.

I was about to start a new thread on distortion and Fourier. Perhaps it would be a mistake without checking the "party line " first.

When I said that, I was not acting as a moderator, but as a member. I guess I still have a right to that, do I?

I also stated in my subsequent post that I'm acting only partially as a moderator. So you shouldn't take it so seriously, dhaen. And what do you mean by "The Emporors New Clothes"?

__________________www.audiosector.com
“Do something really well. See how much time it takes. It might be a product, a work of art, who knows? Then give it away cheaply, just because you feel that it should not cost so much, even if it took a lot of time and expensive materials to make it.” - JC

Peter,
The Emperors New Clothes is a European fable about a vain Emperor, who commissioned the finest clothes to be made for him. He is warned that the fabric is magical, and that only the “faithful” can see it. Thus he is tricked into wearing nothing, and parades in front of his subjects naked. Of course none of his subjects say anything, for fear of being branded unfaithful.

My point is: If Joel can’t hear the difference between capacitor x and capacitor y, he is right to say so, and we should listen; and perhaps even check our findings.

Cathode followers:.
Are a standard tool in the “electronic toolbox” for driving low impedances.
The only other sensible way with AC is with step-down transformers.
They have been used from the start, in many areas of electronics, not just audio.

“Oh, what about SRPP (such as Franks nice circuit in this thread), or mu-follower” I hear people cry?
Well, they are implementations of Cathode Followers too! Are the designers (to many to mention), who use these circuits fools too?

I am well aware that they have had “bad press” in HiFi circles.
Might this have an element of “The Emperors New Clothes”? Well just possibly. For the best explanations I can read against them are: Xyy-san says they’re “clap”, or “don’t use one unless it is properly designed” ie enough current – stiff cathode resistor.
This is where I bang my head against the wall:
Doesn’t that apply to everything?

You cannot look at Cathode followers in isolation: They are always fed by a stage, and feeding a stage.
The distortion of the feeding stage will be lower, because of the higher input impedance of the cathode follower.
The distortion of the stage being fed will be lower because of the low source impedance. Especially DHT’s.
What’s the problem?
Of course the Cathode Follower (like any element) introduces undesirables, but you have to look at the overall picture.

BTW I don’t have any particular love of ‘em. I just use a suitable too for the job in hand, and when a Cathode Follower is the tool, I’ll use it.

I also have 2 criticisms of the moderators:
The first is that they should be clearer what is a moderator’s statement, and what is a personal opinion. Even though they may not have their moderators' badge flashing, they still hold extra weight. Dismissive statements are undesirable from any member, but especially from a moderator.
The second is that since this thread has drifted so far from the original question, it should have been pruned off. You can’t blame any of the contributors for putting their points, even though many (including me) have deviated considerably.

Originally posted by dhaen
Careful Peter, remember The Emporors New Clothes

Cheers,

what I think dhaen means is a story of H C Andersen.

A King was told be some smart crooks, who wanted to make some easy money, that only wise people could see a cloth they had for sale..
Not to be considered stupid, the king said he could see the non-existent cloth.
And he bought the cloth from the crooks.

And the peoples in the country also was told about this.
And noone wanted to be stupid, so they all wanted to "see" the cloth.

All went well until one day the King, should go out in the city with some clothes made of this wonderful cloth.
All said: Oh so beautiful clothes he have!
But a child, who didn't know better, than to believe his eyes, asked his mother:
Why is he naked?
And the people heard the child.
And all had to agree, that in fact the King was naked.

somtimes we humans, agree upon things, not to be regarded stupid
we even have the capability to persuade ourselves that we see things
it can be in many different situations

Originally posted by dhaen Peter,
The Emperors New Clothes is a European fable about a vain Emperor, who commissioned the finest clothes to be made for him. He is warned that the fabric is magical, and that only the “faithful” can see it. Thus he is tricked into wearing nothing, and parades in front of his subjects naked. Of course none of his subjects say anything, for fear of being branded unfaithful.

My point is: If Joel can’t hear the difference between capacitor x and capacitor y, he is right to say so, and we should listen; and perhaps even check our findings.

Now I remember the Emperors story too. I didn't mean to say that Joel shouldn't have expressed his view on not hearing the differences. It just strucks me that he seems to be of proud of it and that I can't understand.

__________________www.audiosector.com
“Do something really well. See how much time it takes. It might be a product, a work of art, who knows? Then give it away cheaply, just because you feel that it should not cost so much, even if it took a lot of time and expensive materials to make it.” - JC

All your points taken, except the comment about the grid resistor. Was that with reference to something in the preamp thread, or a general CF point?

While I was under the car (fixing it) just now, I thought of the ultimate CF circuit: The series (pass) regulator. It has low output impedance, drives a (fairly low) impedance, and is in series with the signal.